Years ago, nephrologist Manjula Tamara, MD, treated a 23-year-old uninsured patient whose kidneys were failing. The patient’s medical options, at that point, were life-long dialysis or a hoped-for kidney transplant – bleak options for such a young person, and ones that adequate preventive care could have been avoided.

That memory, along with the federal government’s recent expansion of Medicaid spurred Tamura as a scientific researcher to pose the question: Does expanded Medicaid coverage translate into better care for low-income patients with chronic diseases, such as kidney disease?

According to the Stanford study published today in the Journal of the American Society of Nephrology, the answer is yes. Using data from national registries, Tamura, who is lead author of the research, and colleagues collected data on the more than 400,000 American adults who developed end-stage renal disease (or ESRD) between 2001 and 2008. As I explained in a release:

Medicaid coverage during those years among low-income, nonelderly adults ranged from 12.2 to 66 percent, depending on the state, with California averaging between 30 and 35 percent. For each additional 10 percent of the low-income, nonelderly population covered by Medicaid, the study found there was a 1.8 percent decrease in ESRD incidence.

The study is particularly timely because states are in the process of deciding whether to adopt the recent changes to Medicaid, which came with the passage of the Affordable Care Act. So far, only about half of the states have. The study discusses these recent changes and what the expansion in Medicaid coverage could mean to low-income Americans with kidney disease, along with patients with other chronic diseases:

Before the Affordable Care Act, only low-income Americans who were pregnant, had a disability or were parents of minors could receive Medicaid coverage if they met their state’s income eligibility levels. States now have the option to increase Medicaid coverage to all adults under the age of 65 with incomes below 133 percent of the poverty level regardless of whether they are pregnant, disabled or parents of minors.

“The care of patients approaching kidney failure or end-stage renal disease is a useful model to study the potential effects of Medicaid expansion on chronic disease care because ESRD care is costly and the quality of pre-ESRD care is tracked nationally,” Tamura said.

What the study did not look at was whether this expansion could ultimately result in financial savings. In the United States, 75 percent of health care dollars goes into the treatment of chronic diseases and these conditions – which include heart disease, diabetes, hypertension, and kidney disease – are all on the rise. In an interview, Tamura suggested that future research on this topic is needed.